Once every spring, and only for two weeks, Texas buckeyes burst spectacularly into bloom. The tree is generally small and understated, with symmetrically grouped pale-green leaves and bunched blossoms; close up, the flowers are tiny and exquisite, with artful splashes of orange-red on the intricate, cream-colored petals. And just a few miles from downtown Dallas, along a stretch of the Trinity River across the levee from Rochester Park, volunteer naturalist Jim Flood guides hikes through the forest to find the buckeyes.

Flood has been leading hikes on the Texas Buckeye Trail for more than 10 years. The forest here is breathtaking: towering oaks, long stretches of bright green rye grass, tangled vines. But this morning, a lone bulldozer was finishing work on the new concrete ADA-approved trail, part of the city's Trinity River Corridor Project. Flood led a group -- families, naturalists, retirees and the AmeriCorps volunteers who will be in Dallas for eight weeks to help with trail work in the Great Trinity Forest -- off the beaten path. We were there to learn about the forest, from edible plants to ancient trees. And, of course, to find the buckeyes.